Structure of the LPS O-chain from Fusobacterium nucleatum strain ATCC 23726 containing a novel 5,7-diamino-3,5,7,9-tetradeoxy-l-gluco-non-2-ulosonic acid presumably having the d-glycero-l-gluco configuration

• Published in: Carbohydrate research Vol. 468; pp. 69 - 72
• Main Authors: Vinogradov, Evgeny, St Michael, Frank, Cox, Andrew D.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.10.2018
• Subjects: Fusobacterium nucleatum; Lipopolysaccharide; NMR spectroscopy; Non-2-ulosonic acid; Polysaccharide; Structure; FucNAc4N; Fusobacterium nucleatum; Non-2-ulosonic acid; Lipopolysaccharide; Fo; GlcN3NA; NMR spectroscopy; Structure; Am; Non; Polysaccharide
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2018.08.011

Fusobacterium nucleatum is an anaerobic bacterium found in the human mouth where it causes periodontitis. It was also found in colorectal cancer tissues and is linked with pregnancy complications, including pre-term and still births. Cell surface structures of the bacterium could be implicated in pathogenesis. Here we report the following structure of the lipopolysaccharide O-chain of a spontaneous streptomycin resistant (SmR) mutant of F. nucleatum strain ATCC 23726: -4-β-Non5Am7Ac-4-β-d-GlcNAcyl3NFoAN-3-β-d-FucNAc4N- where GlcNAcyl3NFoAN indicates 2,3-diamino-2,3-dideoxyglucuronic acid amide with Fo at N-3 being formyl and Acyl at N-2 being propanoyl (∼70%) or butanoyl (∼30%); Non5Am7Ac indicates 7-acetamido-5-acetimidoylamino-3,5,7,9-tetradeoxy-l-gluco-non-2-ulosonic acid presumably having the d-glycero-l-gluco configuration. To our knowledge, no l-gluco isomer of higher sugars of this class as well as no N-propanoyl or N-butanoyl group have so far been found in bacterial polysaccharides. [Display omitted] •An oral pathogen Fusobacterium nucleatum produces LPS containing many unusual sugars.•A novel structure of the LPS O-chain of F. nucleatum ATCC 23726 SmR is presented.•A novel isomer of 5,7-diamino-3,5,7,9-tetradeoxynon-2-ulosonic acid is identified.